import pygame
from pygame.sprite import Sprite

class Ship(Sprite):
    def __init__(self, screen):
        """初始化飞船并设置其初始位置"""
        super().__init__()
        self.screen = screen
        self.image = pygame.image.load('images/ship.bmp')  # 确保有一个ship.bmp图像
        self.rect = self.image.get_rect()
        self.screen_rect = screen.get_rect()

        # 将每艘新飞船放在屏幕底部中央
        self.rect.centerx = self.screen_rect.centerx
        self.rect.bottom = self.screen_rect.bottom

        # 在飞船的属性center中存储小数值
        self.center = float(self.rect.centerx)

        # 移动标志
        self.moving_right = False
        self.moving_left = False

        # 护盾状态
        self.shield_active = False
        self.shield_duration = 3000  # 护盾持续时间（毫秒）
        self.shield_start_time = None

    def update(self):
        """根据移动标志调整飞船的位置"""
        if self.moving_right and self.rect.right < self.screen_rect.right:
            self.center += 1.5
        if self.moving_left and self.rect.left > 0:
            self.center -= 1.5

        # 根据self.center更新rect对象
        self.rect.centerx = self.center

        # 更新护盾状态
        if self.shield_active and pygame.time.get_ticks() - self.shield_start_time > self.shield_duration:
            self.shield_active = False

    def blitme(self):
        """在指定位置绘制飞船"""
        self.screen.blit(self.image, self.rect)
        if self.shield_active:
            pygame.draw.circle(self.screen, (0, 255, 255), self.rect.center, self.rect.width // 2, 2)

    def activate_shield(self):
        """激活护盾"""
        self.shield_active = True
        self.shield_start_time = pygame.time.get_ticks()
